My personal campaign against 768p resolutions

A little background.

A friend of mine has just bought a 14" ultrabook with a 1366*768 display. The usual commerical, mainstream, low quality, standard display.

I suggested him to go for a 1600*900 display or to go for a 13.3 Zenbook (IPS, 1920*1080).

He told me that these resolutions would be too small for him, since at home he uses his Samsung 24" HD LED Display at a 1024*768 resolution, in order to have bigger icons and text.

I told him that this is (almost) a crime, that one should use the native display resolution (1080p in this case) and then rescale it increasing the DPI (120%, 150% or custom).

I know that I'm right, or at least I'm pretty sure of it.
It's just that I don't have enought technical knowledge to answer correctly and without any doubt to his points that I'm posting here.

Therefore I'm asking for your help.
Thanks in advance for your help and sorry for my long post.

Here it's what I told me:

1) High definition display doesn't improve the sharpness of pictures, which depends only from the original (raw) file: if you have a 10 MP photo, human eyes need at least a 40 Mp to see more details, because human eye has a “separation power” of the lines next to each other of a factor 2.5 (?).
So the user won't notice any difference if the same 10 MP photo would seen on a 1080p monitor or in a 768p one.

2) Human eye, at the normal distance from a computer screen (45-50cm), isn't able to distinguish the difference in pixels for displays, of the same size, so it won't make any difference if they have a 1600*900 or a 1366*768 resolution;

3) 1920*1080 resolution produces clear images only for HDTVs of 32” or better and therefore is useless for anything inferior: 1080p resolution exists only for commercial reasons (not the 16:9 format, just the FHD resolution), since the human eye isn't able to notice any difference in displays smaller than 32”.
Therefore 1080p is useless for tablets, smartphones, ultrabooks, notebooks, etc: to prove this, take a 12 MP photo, reduce its resolution by a 50% factor, and put the 2 photos (12 MP vs the “reduced one”) close to each other and you won't notice any difference;

4) 1080p (or higher resolutions) on 4” displays (smartphones) is good only for genetically modified human eyes;

5) Take a 14” display with a 1600*900 native resolution. 1600 pixels are more or less distributed along 300 mm, therefore there are 5.33 pixels/mm: this number is so small that the human eye isn't able to distinguish it, so it doesn't matter if it is 1366 or 1920, the pixels/mm ratio is so small that we can't distinguish them for our typical 45-50cm distance;

6) Retina displays for laptops (like the ones for the Macbook Pros) are useless because from 45 cm nobody is able to distinguish dots which are 0.2mm from each other (like shown here: http://assets.vr-zone.net/13689/ultrabookhires.jpg)

7) In practice, there's no difference on the quality of the images from a 12” Asus Eee PC vs an iPad Retina: you can notice a better quality on the latter only if you pay attention;

8) The difference from a rMBP and a common MBP is noticeable only if one uses a magnifier;

9) If you have a 24” LED HDTV monitor and you set it to its native resolution (1080p), then you set it at 1360*765, using a magnifier in both cases you won't be able to spot any difference in the quality of the text (rescaling algorithms for Windows 7 aren't so efficient);

10) 27” monitors (used by pros working with Photoshop and so on) are “just” 2560*1440 because if you increase pixel size you decrease the contrast;

11) Why should I want to damage my eyesight using super dense displays, at unbearable resolutions (higher than 768p), since the clearer images are just a commercial slogans and no serious reviewer would recommend buying one of them (iPad retinas, rMBR and upcoming IGZO displays and so on)?